Chem - History of the Atom Quiz

First to use the term "atom"

Democritus

Indivisible spheres, "atomos"

Democritus

Atoms are indestructible spheres

Democritus

First atomic theory with experimental evidence

John Dalton

All atoms of the same element are exactly alike

John Dalton

Atoms are indivisible and indestructible particles

John Dalton

Compounds are formed by the joining of atoms of two or more elements

John Dalton

Discovered the electron

J. J. Thomson

Plum Pudding Model

J. J. Thomson

Model described as a "homogeneous mixture of protons and electrons"

J. J. Thomson

Gold Foil Experiment

Ernest Rutherford

Showed the atom is "mostly empty space"

Ernest Rutherford

Discovered the nucleus (dense central core)

Ernest Rutherford

Nuclear Atom

Ernest Rutherford

Proposed electrons orbit in discrete energy levels

Niels Bohr

Planetary Model (electrons orbit like planets)

Niels Bohr

Was mainly concerned with the electrons, not the nucleus

Niels Bohr

Releases electromagnetic energy (photons) when electron falls to a lower level

Niels Bohr

Proved the existence of the neutron

James Chadwick